Use Case

As a Node.js application developer using Client-Side Field Level Encryption on macOS,
I want the published mongodb-client-encryption native prebuilt to load successfully,
so that applications using ClientEncryption can start without downgrading dependencies.

User Experience

Expected:

mongodb-client-encryption should load successfully after a normal npm installation.

Actual:

The macOS prebuilt native addon included with mongodb-client-encryption 7.1.0 and 7.2.0 fails to load with:

Error: dlopen(.../node_modules/mongodb-client-encryption/build/Release/mongocrypt.node, 0x0001):
symbol not found in flat namespace
'_mongocrypt_ctx_explicit_encrypt_expression_init'

code: 'ERR_DLOPEN_FAILED'

Loading the package normally:

node -e "require('mongodb-client-encryption')"

produces a misleading fallback error:

Error: Cannot find module '../build/Debug/mongocrypt.node'

The Release binary exists. The Debug error occurs after bindings.js catches the Release-addon loading failure and attempts to load the nonexistent Debug binary.

This is blocking for applications using ClientEncryption or automatic encryption. The current workaround is to remain on mongodb-client-encryption 7.0.0.

One customer is confirmed affected. The problem reproduces deterministically in an empty npm project with no application dependencies.

Environment

macOS / Darwin: 24.6.0
Node.js: v24.16.0
Node architecture: x64
mongodb-client-encryption: 7.1.0 and 7.2.0
Package manager: npm

The downloaded native addon is a universal macOS binary containing both x86_64 and arm64 architectures.

Reproduction

mkdir mongo-issue
cd mongo-issue
npm init -y
npm install mongodb-client-encryption@7.1.0

node -e "require('./node_modules/mongodb-client-encryption/build/Release/mongocrypt.node')"

Actual result:

Error: dlopen(.../mongocrypt.node, 0x0001):
symbol not found in flat namespace
'_mongocrypt_ctx_explicit_encrypt_expression_init'

The same failure occurs with mongodb-client-encryption 7.2.0.

Version Comparison

mongodb-client-encryption 7.0.0:

npm install mongodb-client-encryption@7.0.0
node -e "require('mongodb-client-encryption'); console.log('7.0.0 loaded')"

Result:

7.0.0 loaded

mongodb-client-encryption 7.1.0:

ERR_DLOPEN_FAILED:
symbol not found in flat namespace
'_mongocrypt_ctx_explicit_encrypt_expression_init'

mongodb-client-encryption 7.2.0:

Fails with the same missing symbol.

This indicates that the regression was introduced in version 7.1.0.

Binary Information

file node_modules/mongodb-client-encryption/build/Release/mongocrypt.node

Mach-O universal binary with 2 architectures:
[x86_64: Mach-O 64-bit bundle x86_64]
[arm64: Mach-O 64-bit bundle arm64]

otool -L node_modules/mongodb-client-encryption/build/Release/mongocrypt.node

/usr/lib/libc++.1.dylib
/usr/lib/libSystem.B.dylib

There is no external libmongocrypt dynamic-library dependency shown by otool.

A previously installed Homebrew libmongocrypt package was removed before repeating the clean-project reproduction. The issue still reproduces.

Dependencies

This may be related to NODE-7569.

NODE-7569 changed how libmongocrypt artifacts are downloaded and was released in mongodb-client-encryption 7.1.0, which is the first affected version.

NODE-5143 concerns build-from-source behavior and incompatible system libmongocrypt installations. It appears separate from this failure because this report concerns the published prebuilt addon in a clean environment.

Risks / Unknowns

It is not yet confirmed whether the issue affects:

• macOS arm64 processes as well as x64 processes
• Node.js 22 as well as Node.js 24
• every supported macOS version

However, the published universal binary contains an unresolved reference to mongocrypt_ctx_explicit_encrypt_expression_init, and the failure reproduces consistently on the environment listed above.